Rhys ap William, who starred in the long-running S4C soap Pobol Y Cwm, was knocked to the ground and left unconscious outside the Admiral Napier pub on Cowbridge Road East just after midnight on Sunday.

The 37-year-old, who works as the Millennium Stadium’s announcer for Wales’ home games, was in a "critical condition" in hospital on Sunday but was yesterday[mon] said to be improving.

His fiancée, Lucy Thomas, said the actor – known as "the voice of the Millennium Stadium" – was yesterday "awake and talking" and was waiting to be moved from the high dependency unit at the University Hospital of Wales, Cardiff, to another ward.

She added: "It has been a massive shock for all of us and everyone involved that somebody could do something like that – and then just walk off.

"Things like this should not happen. You always hear of things happening but you never think of things happening to you."

Rhys – known for playing Cai Rossiter in Pobol y Cwm – had been out with friends watching Wales’ Six Nations victory over Italy before he was assaulted.

Police officers found him outside the Admiral Napier pub in the early hours after they were called to the scene.

Detectives investigating the case say they now want to speak to the man in the CCTV image in connection with the assault, which happened at 12.15am.

A spokeswoman added: "The victim was conveyed to the University Hospital of Wales, Cardiff, where his condition is described as improving.

"Detectives are still appealing for anyone who may have witnessed what happened to come forward.

"In particular would like to hear from a number of people who were in the nearby Miss Millies takeaway at the time including a ginger-haired man."

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